feat: update the on chain blueprint serialization methods for the new way

Author: pedroferreira1

hathorlib/nanocontracts/on_chain_blueprint.py

@@ -42,32 +42,33 @@ class Code(NamedTuple):
     # determines how the content will be interpreted
     kind: CodeKind
 
-    # the actual content, usually the uncompressed code in utf-8 bytes
-    content: bytes
+    # the encoded content, usually encoded implies compressed
+    data: bytes
 
     def __bytes__(self) -> bytes:
-        # Code serialization format: [kind:variable bytes][null byte][content:variable bytes]
+        # Code serialization format: [kind:variable bytes][null byte][data:variable bytes]
         if self.kind is not CodeKind.PYTHON_GZIP:
             raise ValueError('Invalid code kind value')
-        # XXX: zlib is gzip compatible and compresses slightly better
-        zcode = zlib.compress(self.content)
         buf = bytearray()
         buf.extend(bytes(self.kind))
         buf.append(0)
-        buf.extend(zcode)
+        buf.extend(self.data)
         return bytes(buf)
 
     @classmethod
-    def from_bytes(cls, data: bytes, max_length: int) -> 'Code':
-        """ Parses a Code instance from a byte sequence, the length of the data is encoded outside of this class."""
+    def from_bytes(cls, data: bytes) -> 'Code':
+        """ Parses a Code instance from a byte sequence, the length of the data is encoded outside of this class.
+
+        NOTE: This will not validate whether the encoded has a valid compression format. A Validator must be used to
+        check that.
+        """
         data = bytearray(data)
         cut_at = data.index(0)
         kind = CodeKind(data[0:cut_at].decode())
-        dcobj = zlib.decompressobj()
-        content = dcobj.decompress(data[cut_at + 1:], max_length=max_length)
-        if not dcobj.eof:
-            raise ValueError('Decompressed code is too long.')
-        return cls(kind, content)
+        if kind is not CodeKind.PYTHON_GZIP:
+            raise ValueError('Code kind not supported')
+        compressed_code = data[cut_at + 1:]
+        return cls(kind, compressed_code)
 
 
 class OnChainBlueprint(Transaction):
@@ -105,10 +106,7 @@ def deserialize_code(_cls, buf: bytes) -> tuple[Code, bytes]:
         if serialized_code_len > max_serialized_code_len:
             raise ValueError(f'compressed code data is too large: {serialized_code_len} > {max_serialized_code_len}')
         serialized_code, buf = unpack_len(serialized_code_len, buf)
-        code = Code.from_bytes(
-            serialized_code,
-            max_length=settings.NC_ON_CHAIN_BLUEPRINT_CODE_MAX_SIZE_UNCOMPRESSED,
-        )
+        code = Code.from_bytes(serialized_code)
         return code, buf
 
     def _serialize_ocb(self, *, skip_signature: bool = False) -> bytes: